Path: utzoo!attcan!uunet!samsung!uakari.primate.wisc.edu!dali.cs.montana.edu!milton!forbis
From: forbis@milton.u.washington.edu (Gary Forbis)
Newsgroups: comp.ai
Subject: Re: Some thoughts on the Searle controversy
Message-ID: <5187@milton.u.washington.edu>
Date: 17 Jul 90 19:43:15 GMT
References: <1597@oravax.UUCP> <5146@milton.u.washington.edu> <1598@oravax.UUCP>
Organization: University of Washington, Seattle
Lines: 56

In article <1598@oravax.UUCP> daryl@oravax.UUCP (Steven Daryl McCullough) writes:
>In article <5146@milton.u.washington.edu>, forbis@milton.u.washington.edu (Gary Forbis)
>writes:
>> In article <1597@oravax.UUCP> daryl@oravax.UUCP (Steven Daryl McCullough) writes:
>> >Every programming language that can be compiled or interpreted must
>> >have an operational semantics, and so every program automatically has
>> >a semantic, as well as a syntactic, component.
>> 
>> This is true but insufficient to describe what one means when one talks
>> about a program.
>
>I'm not sure what you mean by this. For many (most? all?) purposes,
>the operational semantics is all you need to know.

It certainly isn't.  I spend most of my time deciding how a particular program
should behave within a given context.  I write the syntax such that (to the
best of my abilities) the operational semantics agree with the behaviors I
am modelling.  One cannot know by the operational semantics alone that the
program has a bug.  What does it mean for a program to have a bug if the
program is the syntax and the associated operational semantics?

>No, to me the important fact about a program is not its syntax, but
>its operational semantics; how a machine running the program would
>behave.

To me the important fact about a program is how it is intended to behave.

>Our only
>disagreement is that you think that the programmer has the final say
>on what the "real" semantics is, while I don't agree; to me, any
>consistent interpretation is as correct as any other.

How can one have a consistent interpretation and a bug at the same time?
It is through the inconsistencies between interpretation and operational
semantics we know bugs exist.  I know when a program I did not write has
a bug in it becuase I know the programmer's intent.

>Who made the programmer God? If I pay for a program, I can interpret
>it any way I want to. It seems to me that any interpretation that can
>be consistently maintained is "correct", and this includes both
>statements in English and programs.

Don't ask me to fix any bugs in a program you insist in interpreting 
in a way other than the programmer intends.

>The inputs to a computer are not English, they are electrical signals.

I don't know about you but I poke keys with English symbols on them and
the screen displays the same symbols.  The input to my computer is
English symbols which the machine converts to electrical signals for
processing.  I am pleased by the machine's consideration in converting
these signals back into English symbols when it is done with them.

>Daryl McCullough

--gary forbis@milton.u.washington.edu